United Kingdom, March 6 -- Lisa Rinna is able to laugh off speculation about her marriage.

The 62-year-old reality star has rubbished various online rumours about her 29-year marriage to actor Harry Hamlin - including social media theories that he's been unfaithful.

In her new memoir, You Better Believe I'm Gonna Talk About It, Lisa says: "There are some cave-dwelling internet trolls who live to tear us down and start rumours. I get that. It's way more fun to see fights than cuddles."

Lisa - who has Delilah Belle, 27, and Amelia, 24, with Harry - actually finds the speculation to be more amusing than hurtful.

She explained: "So I just laugh when I read that we don't live together anymore, he's having multiple affairs in Canada, and he...